. Write a shell script that copies the file named by its first argument to a file with the same name with the filename extension of .bak. Thus, if you call the script with the argument first (and a file named first exists in the working directory), after the script runs you would have two files: first and first. bak. Demonstrate that the script works properly

Hi! The requirement of this question is a simple shell script that makes a copy of a file if it exists in the directory. The main command for this is "cp <file_to_copy> <copy_filename>"  

Explanation:

We can write a code below to implement this in a file called "backup_script". The first argument to the script is taken as the fie_name. Then a check is done to see if the file exists with the "[-f file_name]" code, and the file is copied with a ".bak" if true. A success message is finally printed out to the user.

./backup_script

#! /bin/bash

set file_name = $1

if [ -f file_name ]; then

 cp file_name file_name.bak

fi

if [ -f file_name.bak ]; then

 echo "File successfully copied"

fi

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